Valve



Jan. 9, 1940. v. HOOPER Er AL 2,186,925

' VALVE Filed May 11, 1938 3 shets-sheet 1 a 25 g5 255 802 fg '2, 6^ 25d265/1242525@ Jan. 9, 1940.

y. l. HooPER x-:r Al. 2,185,925

VALVE Filed May ll, 1938 5 Sheets-Shea?l 2 as y. 55

Jan- 9, 1940. v. l. HooPl-:R ET AL VALVE Filed May ll, 1938 3Sheets-Sheet 3 Patented jan. 9, 1.940

`finta25 PATENT OFFICE vALvE Y Virgil I. Hooper, Gordon, Tex., and G.

Hooper, Sarepta, La., assignors to The Bastian- Blessing Company,Chicago, Ill., a corporation of Illinois l 9 Claims. Our inventionrelates to a loading assembly for -thegloading and unloading of liquidsorgases or `mixed liquids andv gases. One purpose is the provision of animproved loading and unloading assembly for loading such materials intoa tank I, Another"purp0se is'the provision of improved A vstorage orshipping container for liquids, gases or the like closedto theatmosphereduring the insertion or removal of the fittings necessary tofeed nuids to or remove them from al tank or closed space. z

Another purpose is the provision of an improved means "for handling lliquids, gases, or mixed I liquids or gases for shipment or storage,whereby the, release of any substantial part of such materialsisprevented during either loading or unloading or both.

Another purpose is the provision of improved valve means for tanks, carsand the like.

Other purposes will appear from time to -time in the course of thespecification and claims'. 4We illustrate our invention more or lessdiagrammatically in the accompanying drawings -whereinz 1 Figure 1 is apartiaiside' elevacin with parts broken away, illustrating theapplication of our improved valve means to atankear;v

. Figure 2 is a vertical longitudinal vsection through a part of thedome. 0f4v a tank car, illustrating the tank car in conditie.'forshipment;

' Figure 3 is a vertical section', illustrating part of the loadingassembly applied -to the'loading `I it22 to receive correspondingthreads oraclei Figure 4 isa partial section,illustratingsome-surefplugvhaving an upper enlargement or 40 of the parts shown inFigure 3 in a diilferentpol' inlet;

sition;

Figure 5 is a section on the line 5-5 of Fig I ure 4;

Figure 6 is a vertical section through a variant assembly Figure '7illustrates. thevvaria'nt assembly when the car is ready for shipment;vand Figure 8 is a detail.

Like parts will be indicated by like symbols including ilxed tanks,buried tanks and the like.

Application M ay 11, 1938, Serial No. 207,419

` `head 2l with a downward shoulder 25. The portion 2i!v is inwardlyscrew-threaded as at 26 and 30 which forms a part of theloading assemblybelow described. 'I'hus the. iltting receives se- Referring to thedrawings, I indicates any suitable tank herein shown for the purpose ofillustration as the type of tank which is employed in connection withtank cars. 5 is a tank car vdome shown as having a removable cover plate6 nor- 5 mally held in position by any suitable nuts and bolts 1, 8. Itwill be understood that any other suitable securing means may beemployed,

Referring to Figure 1, we illustrate a loading and unloadingI assemblygenerally-indicated as 10 A and a gauging and vent assembly generallyindicated asl B; The assemblyy Aistheprimary subject matter of thepresent applicationandjthe vent assembly B will be described onlycursorily as it forms the subject matter ofa separate ap-` 15 Plication.l

Referring to Figure 2, the'eduction pipe Il which will be understoodtoterminate closely adjacent the bottom of-the tank is shown asscrewthreaded or otherwisesecured to' Vthe ange I5 which is secured tothe inner surface of the top of the dome. It may bewe1ded, bolted orlotherwise secured. vItis in line, however, with the loading aperture 'I6formed inv the domev 5. Alinedabove the aperture I6 we illustrate aiiange member I1 in which is positioned the iltting gen'.- erallyindicated as I8 which is shown on a larger scale at the bottom of Figure3. It may include for example a lower portion I9 of minimum diamf eterand an upper and preferably concentric portion 20 of greater diameter. II a is an excess pressure valve. In the particular embodiment shown vinvFigure 3 we illustrate the portion laas outwardly screw#- threaded at2| and in screw-threaded relationship. 35 with correspondingv threadsformed in the passage aperture of the flange I1. The inner face o'i. themember I9 is shown as screwf'threaded as v is formed tov receive thethreads 21 ofany suitable closure cap 28, as shown invFigure;2,-wh`enlthe assembly is removed and the closure is substituted. Also, the samescrew-threading is adapted to receive the threads 29 of the wing nut Alectively either the closure cap 28 or the loading 50 assembly of Figure3.

^ vIn order to provide a proper seal for the contents of the tank duringshipment, we may providethe closure 28 with a plurality of apertures'28a about the flange of the closure cap. Through .1

these apertures 28a may pass any suitable sealing strip 28h which inturn may be looped through an eye 28o mounted on or secured to theiiange or fitting or 6D. 28d is any suitable seal in the loop or band2Gb.

Assume that the tank is being shipped, either full or empty, it ispreferably shipped with the closure 28 in place as shown in Figure 2 andwith the closure plug 23 rmly screwed down against the gasket 3 I. Thegasket 3| is shown as received n a recess 3|a in the plug 23 wherebywhen the plug is raised from its seat it carries the gasket with it. Thegasket 3| is shown as concentrically located within the outer gasket3|b, but if desired a single gasket may be employed. In any event, thesingle gasket or the two gaskets form a seal and the parts are soproportioned that when the cap 28 is screwed into position its loweredge also abuts against the outer gasket, both gaskets resting upon thesingle annular supporting or sealing surface 32, which is preferably butnot necessarily perpendicular to the axis of the assembly. The gasketmeans herein shown are advantageous but a tapered thread or a groundjoint or any other suitable sealing means may be employed.

Assuming that the outer closure 28 has been removed, as shown in Figure3, a passage member 33 may be applied to the fitting. It is shown ashaving a bottom ange 01 shoulder 34 against which the wing nut 3|] abutsand which preferably conforms to the surface 32' or to the gaskets 3| or3|b, whereby when the wing nut 3D is tightened the member 33 is lockedeffectively in relation to the fitting |8 and surrounds the plug 23, 24.We illustrate the member 33 as having applied thereto an upper portionor extension 35 which may have a side passage or lateral extension orother outlet portion 36. We illustrate it as screw-threaded as at 31 toreceive any suitable valve assembly 38, as shown in Figures 1 and 3.I'his valve assembly might, of course, be located intermediate the endsof the below described loading or unloading hose 5| or at the oppositeend of the hose. We find it convenient to have it associated directlywith the passage members 33, 35. It is important in any event thatclosure means be provided so that the space within the members 33, 35which constitutes a passage may be closed to the atmosphere and may alsobe cut oi from the loading or unloading zone. The diameter of theenlargement 24 of the closure plug 23 is slightly less than the interiordiameter of the members 33, 35.

We illustrate venting means adaptable to provide atmospheric or outsidecommunication with the space between the closure 23 and the valve 38. Weillustrate for example an outlet passage 40 of restricted diameter whichis controlled by any suitable valve mechanism generally indicated as at4| and having an exterior handle 42. It will be understood, however,that any suitable means may be employed whereby the operator can permitthe escape 0f gases from the space within the members 33. 35. This is ofimportance in connection with the application of the loading assembly.It is also important as permitting the user to determine whether or notthe plug 23 is tightly in position at a time when the members 33, 35 arein the position in which they are shown in Figure 3. It is also possibleto employ this valve or vent to drain liquid from the said space and, ingeneral, to relieve pressure from that space when necessary.

It will be understood that whereas we have shown a screw-threadedclosure plug 23, other closure means might be employed. However, ascrew-threaded plug is convenient and eflicient. When such a plug isemployed, it is necessary to unscrew it while the assembly 33, 35 is inplace and to position it out of the line of flow between the tank andthe passage 36. We therefore provide a control stem 24a. which may berotatably and slidably mounted in the end 43 of the member 35. The lowerend of the stem may be squared or otherwise formed as at 44 in order topenetrate the corresponding aperture 45 of the plug 23, 24. Thus whenthe stem 24a is rotated it rotates the plug 23.

The aperture 45 of the plug may be provided with a recess 46 to receivethe thrust balls 41 which serve as a locking means to prevent the plug23 from dropping from the end of the stem after it has been unscrewed orreleased. Similar balls 48 are located in a somewhat higher portion ofthe stem 24a and are adapted, as shown in FigureI 4, to penetrate thelocking channel 49 in the member 43. Thus the operator has merely towithdraw the stem 24a to topmost position, as limited by the abutmentmember 50 in order to lock it and the plug 23 in an upward positionabove and out of line with the passage f6 and the ow of material intoand out of the ank.

We thus provide means for putting the interior of the passage formed bythe members 33, 35 and 36 into communication with the interior of thetank while maintaining such space closed, and while preventing anyescape of gases from the interior 'of the tank. It will be understoodthat we may obtain the same result through different means, but thescrew-threaded plug is illustrated as a practical and operative solutionof the problem.

Assume that the closure 28 hasbeen removed and the loading assembly,including the parts 33 and 35 has been applied, the interior of theloading assembly is thereafter put in communication with the interior ofthe tank. The operator can connect the valve 38 with any suitable sourceof liquid or gas to be loaded or transported, for example by the pipe orhose 5|. When all connections have been made, the valve 38 can be openedand pressure may be applied by gravity or otherwise to cause the liquidor gas to iow inwardly along the hose 5| through the open valve 38inwardly along the passage 36 and downwardly through the member 33, andthus into the tank which can then be lled to any predetermined level orpressure.

The operator can sample or gauge, if desired, by employing the slip tubegauge |04 which will later be described. In handling some substances,however, no separate gauging or sampling or venting means are necessaryand the assembly B of Figure l may be dispensed with. It will beunderstood, also, that under some circumstances and with some substancesthe eduction pipe may be omitted.

When the tank is lled to the desired level or pressure, the valve 38 canbe closed and the plug 23 thrust into locking position and rotated bythe stem 24a until firmly locked. Ihe valve 4| can then be employed todetermine whether or not the plug is fully locked and also to exhaustpressure from the space within the members 33 and 35 above the plugprior to removing the loading assembly. Thereafter, the wing nut 3U canbe rotated to releasing position and the Referring to the vent side orthe assembly B,

it will not be described in great detail as it does not of itself formpart of the present invention and is described and claimed in aco-pending application Weillustrate it, however, asincluding a flangevor passage member 60 which may be secured to or may be formed integrallywith the Vfdome 5. Secured to the member 60 is a fitting generallyindicated'as 6I and generally like the fitting |8 of Figure 3. It may beinteriorly screivthreaded to receive any suitable plug or closure 66, 61resembling the plug 23,24. Similarly, the passage member 14 may beremovably secured to the fitting 6| as by means of the wing nut 13. Avalve 16 closes the upperA portion of the passage member 14. The valve,which may be a gate valve, is controlled by any suitable externalhandle- 18. An upper passage or elbow 19 is positioned thereabove,having a lateral passage having a valve 82 controlled by the handle 63and in communication with the hose Sla-which may, if desired, haveassociated :herewith any suitable back pressure regulator Slidabledownwardly through the assembly above described is a slip tube gauge |04having calibrations and a bottom member or abutment |06. If desired, apump cylinder |22 may be mounted on the upper end of the slip vtubegauge |04 and any suitable handle |25 may be employed to actuate it anddraw` up the liquid through the tube |04 in the event that there isinsumcient pressure within the tank to cause the liquid to rise in thetube.; Theescape of the liquid may be controlledfor-exampleby anysuitable valve assembly ||3 with the control handle or knob 6. It' willbe understood that when the above described venting and gauging andsampling assembly is in position, gasmay bereleased through the hose 5|a and by meansof the tube |04 samples may be-taken fromtime to timey andthe level ofy thel liquid inthe tank-may be" determined. When the tankis prepared forshipf ping the above assembly is removed and a closure28, similar to that for assembly A, is screwed into the fitting 6|.

In Figures 6 and 7 we illustrate an alternative form of our invention.Whereas inl the form 'of' Figures 1 and following, a closed plug 23 isernployed, we can use a valve assembly which is externally operable andwhich is secured to or permanently left onthe tank. Referringl tovFig-1f; ure 6, a nipple |50 extends upwardly from the" v It may forexample-be screwthreadedtank. into a flange |5| |5|a indicates vanysuitable eduction pipe, which extends to the bottom of the tank andwhich is employed with materials and under circumstances rendering aneductionv pipe necessary. |5|b indicates an excess pressure valve whichserves to prevent escape of liquid in the event of breakage or prematureopening of the valve assembly.

|52 is any suitable valve housing having a valve |53 therein shown ascontrolled by theeirf4 terior handle |54. Whereas we illustrate` inllig-A ure 6 a stop cock, it will be understoodv that any..

is screw-threaded as at |60 to receive a valve is locked vvterior of theilttingvila'nge.` v f vailingly.v shipped inl insulated containers.l

housing |6| having an exteriorly operable valve |62. This valve is alsoshown as a stop cock but any suitable valve such as a gate valve may besubstituted therefor. v

In communication with the passage |59 through the valve housing |6| isany suitable loading and unloadinghose |63 which may extend to a sourceof liquid or iiuid supply or, when the assembly is being used forunloading, may

lead to any suitable delivery or storage zone.-

The interior of the passage member |51 between the valves |53 and`|62vis provided with an additional outlet or vent |64 controlled by anysultable valve having for example an external handle |65. It will beunderstood that the vent |64 is of substantialy smaller cross sectionalarea than the areas controlled by the valves |53 or |62. It may beemployed to vent the interior of the passage member |51 to theatmosphere or otherwise.

Referring to Figure 7, vit will be understood that the nipple |50 whenthe passage member |51 is removed, may be closed by having the valve |53turned to the closed position. An additional closure may be employed inthe shape of the screwthreaded plug |80 which is received in the threads|55 -of the valve housing flange |55.

'I'hus the form of Figures 6 and 7 differs from the or passage ttingassociated with the tank, we

wish these terms to be interpreted with sulcient' breadth'to include theformation of'a passage., integral with the tankor integral with thedomel i cover or coverplate, it being a matter of. choice as lto whetherornot suchA a tting or its-equivalent be maderemovable or beseparately'formed' and thereafter applied permanently tothe tank, -orit' formed as part of thetank, Adome or cover. Y'. .t .Y

scribethe plug or closure as screw-threaded, it

Where inthe speclilcation and claims 'we lde-l lof' will' be understoodthat we wish such term to be vinterpreted with sufiicient breadth tocover any locking arrangement wherebyV the plug or.. closureA orvunlocked inl response to rotationr f' 1 v FOI x'amplgffit willbeiinderstoodthat wherey 1 wey employ vvanky externally .screw-threadedwing l '..f-.fnut in', .connection e rivith aan; iriteriuillyl` f.screwj f' .e threaded -fitting 20, lthe relation of the parts may f bereversed and the wing nutfand the'housing 4 thereof.

may engage the exterior rather thangg'the in It will be realized thatwhereas in the size, shape, number. and disposition of parts without.departing :from the spirit of our invention. We 1therefore 'wish ourdescription and drawings to bet'akenfas'fin a broad sense illustra# tiveor diagrammatic. --rather than aslimiting `us, to our precise 'thomasandoperation; of. e.

ounjinveri't'ion" -ar'e as follows:

we'havvpdeA.. scribed and illustrateda practical -r and-.op erativedevice, nevertheless many changesmayfbe made The prime purpose of` ourA.invention is to avoid ftheenormous'losses which take place in thecurrent handling `of volatile liquids such as gasoline, casingheadgasoline and the like, which are pre- In handling highly volatileliquids, it is exceedingly disadvantageous and wasteful to permit suchliquids or the gases therein or associated therelid with to exhaust tothe atmosphere whether during loading or unloading. Our inventionenables an operator to load volatile liquids to a tank and to unloadthem without at any time permitting the storage or shipping zone to bein direct communication with or to exhaust to the atmosphere. Ourinvention is applicable not merely to shipping volatile liquids frompoint to point, but for iixed or buried storage systems from whichliquids or gases are thereafter dispensed or used. It may be used inconnection with buried butane or propane systems used for house heating,cooking or the like.

A practical advantage of our loading assembly is that it can be appliedto and used in connection with existing equipment, such as tank bars,Without any substantial modification of the present structures andwithout the necessity of applying new and expensive equipment to tanks,tank cars and the like. A further advantage is that our removable valveassembly or assemblies can be kept at loading or unloading points andmay be carried to or removed from xed tanks, Whereby a given assembly orgroup of assemblies may be employed in connection with a large number ofdifferent cars, tanks or the like.

We can readily adapt existing cars or tanks to our invention by applyingto them the preferably removable and semi-fixed iitting I9, 20 with theclosure plug 23 and the outer cover 28. Thus only inexpensive elementsare applied to or are moved with or are installed on the tank cars ortanks while the more expensive and delicate valve assemblies such as areshown at A in Figure 1 may be applied to the tank or car at the time ofloading or unloading and may be removed when the loading or unloadingoperation is completed and may be stored and serviced at the loading orunloading point. Thus they are at all times in the hands of competentoperators and are not subjected to the hazards of travel or to the abusewhich they would receive at the hands of employees who have no directresponsibility for them. It will be clear that a large number of carscan be handled by the employment of a small number of loading orunloading assemblies or units.

In handling volatile liquids and particularly iniiammable liquids, theprevention of any substantial exhaustion to the atmosphere results in anenormous saving of the substances handled. It also greatly increasessafety, since it prevents the exhaustion to the atmosphere of the largequantities of inflammable gases which are released in current practice.A further advantage is the great saving in time.

As an example of the problem faced, during the loading and transit ofcasinghead gasoline, a considerable portion of the gasoline is driveninto vapor so that when the tank car arrives at its destination a verysubstantial pressure has been built up in the tank. Prevailingly in thepresent practice the closure cap is removed and the gaseous contentsunder pressure are simply wasted to the atmosphere. This venting has tobe permitted since otherwise it would be dangerous for the operator toremove the dome c over 6. Some cars 'are even provided with a safetycover which prevents their removal until this pressure is vented oi.This venting may require several hours, which involves a substantialloss of time. The presence of the vapor in the atmosphere is a hazardsince a spark from a passing locomotive may ignite the vapor. As amatter of fact, many lives have been lost from this cause. The wastageof material is great. In hot weather, cases are known Where as much as3,000 gallons of gasoline have been wasted from a ten thousand gallonload. The wastage is seldom less than 300 gallons per load, even in cold5 weather. This involves not merely a money loss to the shipper but awaste of a limited natural resource. A

Whereas our invention is particularly applicable to and valuable withthe handling of volatile and inflammable liquids, it lends itself to theeconomical handling of a wide variety of liquids, both Where pressure ispresent and where pressure is absent. Lubricating oils, for example, maybe efficiently handled through our removable valve assembly. A partiallist of substances which .can advantageously be handled includesgasoline, propane, butane, crude oil, lubricating oil, alcohols,volatile solvents, acids, malodorants, poison gases, chlorine gas, andliqueed gases in general.

'I'he excess pressure valve lla is useful as preventing undesired escapeof the contents of the tank in the event that the valve assembly isbroken off or prematurely removed or improperly opened.

We claim:

1. In a removable valve assembly for a tank or the like having anaperture and a closure therefor, a passage member and means forremovably securing the passage member in sealing relation to theaperture of the tank, While such aperture is closed, means supportedupon said passage member for non-rotatably engaging the closure cf suchaperture for removing it from a 35 position sealing such opening or forfully restoring the closure to said position While said passage memberis in place, said means including an actuating part exterior of saidpassage member, an additional passage member in fluid ow communicationwith said first-mentioned passage member, a separate closure for saidadditional passage member independent of said iirst closure, and meansfor actuating said separate lclosure to move it into and out of closingposition.

2. In a -removable valve assembly for a tank or the like having anaperture and a closure therefor, a passage member and means forremovably securing the passage member in sealing relation to theaperture of the tank, While such aperture is closed, means supportedupon said passage member for non-rotatably engaging the closure of suchaperture for removing it from a position sealing such opening or forfully restoring the closure to said position While said passage memberis in place, said means including an actuating part exterior of saidpassage member, an additional passage member in uid iiow communicationwith said first-mentioned passage member, 00 a separate closure for saidadditional passage member independent of vsaid rst closure, means foractuating said separate closure to move it into and out of closingposition, independent means for venting pressure to the air from the 05interior of said first mentioned passage member, and means for operatingsaid venting means independently of the closure for the tank and forsaid additional passage member.

3. In a removable valve assembly for a tank 70 or the like having anaperture and a closure therefor, a passage member and means forremovably securing the passage member in sealing relation to theaperture of the tank, While such aperture is closed, means supportedupon said passage member for non-rotatably engaging the closure of suchaperture for removing it from a position sealing .such opening or forfully restoring the closure to said position while said passage memberis in place, said means including an actuating part exterior of saidpassage member, an additional passage member in fluid flow communicationwith said first-mentioned passage member, a separate closure for saidadditional passagemember independent of said first closure, means foractuating said separate closure to move it into and out of closingposition, independent means 'for venting pressure to the air from4 theinterior of said first mentioned passage member, Asaid venting meansincluding an outlet of substantially reduced cross-section in relationto the crossv sectional area of said additional passage member, andmeans for operating said venting means vindependently of the closure forthe tank and for said additional passage member. l

4.The combination with the filling opening structure of a tank and aclosure for such structure provided with a socket, of a removable valveassembly detachably secured to said structure, said assembly comprisinga passage member, an operating stem traversing said passage member andhaving one end projecting therefrom, means secured to said end formoving said stem, means at the other end of said stem removably receivedin said socket, means detachably locking the second-mentioned means insaid socket, and an additional passage member in fluid fiowcommunication withl said first mentioned passage member, and independentvalve means for said additional passage member.

5. The combinationwiththefillingopeningstructure of a tank and a closurefor such structure provided With a socket, of a removable valve assemblydetachably secured to said structure,said assembly comprising a passagemember, an operating stem traversing said passage member and having oneend projecting therefrom, means secured to said end for moving saidstem, means at the other end of said stem removably received in saidsocket, means detachably locking the second-mentioned means in saidsocket, an additional passage member in 4fluid fiow communication withsaid first mentioned passage member, valve means therefor, andadditional means for venting pressure from the interior of saidfirst'mentioned passage member to the open air.

6. In a removable valve assembly for vtanks and the like, a passagefitting on the tank, a closure plug removably screw-threaded in thepassage of the fitting, said fitting including an internally threadedportion of greater diameter than saidA plug, a passage member and meansfor releasably securing it to said last-mentioned threaded portion ofthe fitting while the plug is in place, an operating element traversingsaid passage member and having one end projecting therefrom, meanssecured to said end for moving said element, and means for securing theoppositel end of said element detachably and non-rotatably to theclosure plug of said fitting to permit said plug to be removed from aposition sealing said fitting or restored to said position. v

7. In a removable valve assembly for tanks and the like, a passagefitting on the tank, a threaded closure plug bodily and removablyscrew-threaded in the passage ofthe fitting, said fitting including anadditional interiorly uscrew-threaded portion of greater diameter thanthat in whichthe closure plug is screw-threaded, a passage member, andmeans for rotatably securing it vto said fitting while the plug is inplace, an operating element traversing said passage member and havingone end projecting therefrom, means secured to said end for moving saidelement, meansfor securing ed portion of the fitting, and anexteriorlyscrewthreaded nut surrounding said passage member above saidshoulder and threadedly engaged with the interiorly screw-threadedportion of the fitting whereby to seal the passageV member to thefitting while the plug is in place.

8. In a removable valve assembly for tanks and 'the like, a removablepassage fitting on the tank,

a bodily removable closure plug screw-threaded in the passage of thefitting, a passage member and means for removably securing it to thefitting while the plug is in position within the fitting, the interiordiameter of the passage member being greater than the exterior diameterof the plug, 3

an operating element traversing said passage member and having one endprojecting therefrom, means secured to said end for moving said element,means'for securing the opposite end of said element detachably andnon-rotatably to the closure plug to permit the closure plug to beremoved from ajposition sealing said fitting or restored to saidposition, a lateral passage extending from said first passage member anda valve therefor, a vent member in communication with said passagemember, and a valve for controlling said vent member and means foractuating said valve to vent said passage member to the air,irrespective of the position of said plug and of the first-mentionedvalve.

9. In a removable valve assembly for tanks and the like, a -removablepassage fitting on the tank, a closure plug bodily removable andscrew-threadingly mounted inthe passage of the fitting, a passage memberand lmeans for removably securing it to the said fitting while the plugis in position within the fitting, an operating element traversing saidpassage. member and having one end projected therefrom, means secured tosaid end for moving said element, means for securing the opposite end ofsaid element detachably and non-rotatably in the closure plug of saidfitting to permit the closure plug to be removed from a position sealingsaid fitting or restored to said position, an additional passage memberin communication with said first passage member, a valve controllingsaid second passage member and carried thereby, said first passagemember being provided with an additional outlet 'passage of restricted.diameter in communication with the space between said valve and saidclosure plug, and a valve controlling said last mentioned passage andmeans for actuating it from the outside to cause venting to the air.

VIRGIL I. HOOPER.

LOUIS G. HOOPER.

